As babies, 'Nemo' clownfish embark on epic journeys

In the movie "Finding Nemo," a father clownfish swims across the ocean to find the son he lost, but in reality, it's the babies that make long journeys to survive, AFP reports.

In their first days of life, clownfish larvae can swim up to 400 kilometers (250 miles) in order to find a home, said the study out Wednesday in the journal PLOS ONE.

"That's an epic journey for these little dudes," said co-author Stephen Simpson from the University of Exeter.

"When they make it back to the reef, they're only a few millimeters long and they have only a few days to make it there so they must be using ocean currents to assist their migration."

Indeed, researchers studying the fish off the waters of Oman saw that there were just two coral reef systems along the coast, separated by 400 kilometers (250 miles) of ocean.

Divers collected tissue samples from almost 400 clownfish, by taking a small fin clip for DNA analysis before releasing the fish again.

They used DNA fingerprinting to identify fish that were migrating from one population to another, and found that six percent of the fish sampled had made this long journey.

"In order to persist, fish must be migrating between these two populations," Simpson said.

Researchers said that much like in the 2003 Disney movie, clownfish live most of their adult lives in anemone.

They also rely heavily on ocean currents to take them from place to place. Most of the migrant fish traveled from north to south, corresponding with the dominant ocean currents in the region that are driven by the winter monsoon.

But unlike in the movie, their travels only take place when the fish are tiny.

Researchers said the findings will help establish marine protected areas and has added to scientists' understanding of how fish adapt to their environment.